After Eating a Large Meal of Pasta, an Individual's Blood

After eating a large meal of pasta, an individual's blood sugar levels are elevated. In response to this, the pancreas secretes a hormone called insulin, which acts to lower blood sugar levels. Once the blood sugar levels drop to the normal level, the pancreas stops secreting insulin. This is an example of

A) a positive feedback loop.
B) a negative feedback loop.
C) acid- base imbalance.
D) reactions between carbon monoxide and acids.
E) energy being made into proteins.